"A scan on Monday revealed that he has an unstable joint and that he will require surgery. He is expected to be out of rugby for between 10 and 12 weeks."

Ulster centre Stuart Olding will also miss the Six Nations with elbow ligament damage that could see him out for three months.

Connacht confirmed a "low-grade ankle sprain" for centre Robbie Henshaw in their weekend European clash with Exeter.

The powerful midfielder could yet recover in time for Ireland's Six Nations opener, but will face a clear fitness battle.

The glut of injuries could see Ireland head coach Schmidt pair Ulster's utility back Jared Payne and Leinster centre Gordon D'Arcy for the upcoming trip to Rome.

"Stuart Olding also sustained an elbow injury against Toulon," Ulster confirmed in their statement. "A scan has confirmed that he has significant ligament damage that will require surgery to repair. He is also expected to be out for between 10 and 12 weeks."

Athlone-born Henshaw, who is viewed as the long-term successor to Brian O'Driscoll, has not suffered long-term damage, but will still have to work hard to face the Azzurri in Rome.